JPH0245094Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a webbing take-up device for use in a seat belt device for protecting an occupant in a vehicle emergency, and for winding webbing for restraining an occupant.

In a webbing retractor used in a seat belt device, a ratchet foil is fixed to a retracting shaft that winds up the webbing, and a lock bar engages with the ratchet foil in the event of a vehicle emergency to stop the rotation of the webbing. . As a result, the occupant is reliably restrained by the webbing, improving safety.

However, although this meshing means consisting of a ratchet wheel fixed to the winding shaft and a lock bar can ensure the locking of the winding shaft, it has the disadvantage of increasing the outer diameter of the webbing winding device.

Therefore, a webbing take-up device has been proposed in which a lock plate held on the take-up shaft engages with an internally toothed ratchet to stop the rotation of the webbing pull-out of the take-up shaft. This winding device is small and has a stable response acceleration, thereby improving passenger safety. However, since the structure is such that a plate with internal ratchets carved thereon is fixed to the take-up device frame with rivets or the like, the number of parts is large and assembly is complicated.

The present invention takes the above facts into account, and provides a webbing take-up device that has a small number of parts, is easy to assemble, and has improved strength despite using a combination of a lock plate and an internal tooth ratchet. is the purpose.

A webbing take-up device according to the present invention includes a take-up shaft that is extended from a frame and is rotatably supported between a pair of leg plates formed to face each other, and that winds occupant restraint webbing, and the take-up shaft. A lock plate that rotates with the webbing and prevents the rotation of the take-up shaft in the webbing pulling direction when the rotation is stopped, and an internally toothed ratchet that is attached to one of the pair of leg plates and that engages with the lock plate to stop the rotation. and an extension part that integrally extends from the main body part, spans over the other leg plate in a state substantially parallel to the winding shaft, and is fixed to the other leg plate, The extension part supports the torsional force between the one leg plate and the other leg plate that acts through the main body when the rotation of the winding shaft is stopped by the lock plate. It has an internal tooth plate that reinforces the leg plate.

Further, in this case, the internally toothed plate is attached to the leg plate by being inserted between the leg plate and a bracket whose corner portion integrally projects to the outside of one of the leg plates.

This improves the strength and rigidity between the leg plates and reduces the number of parts.

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIGS. 1 to 4, the webbing retractor 10 according to this embodiment has a frame 12 fixed to a vehicle body 16 with mounting bolts 14. As shown in FIGS.

A circular hole 21 is coaxially bored in the leg plates 18 and 20 extending parallel to each other from both sides of the frame 12, and a winding shaft 22 is pivotally supported. One end of an occupant restraining webbing 24 is wound in layers around the center of the winding shaft 22.

Further, the inner end of a mainspring spring 26 is attached to the end of the winding shaft 22 that passes through the leg plate 20, and the outer end of this mainspring spring is locked to a spring case 28 fixed to the leg plate 20. Therefore, the winding shaft 22 is in the winding direction of the webbing 24 (direction of arrow A in FIGS. 2 and 3).
is being energized. An internal tooth ratchet plate 30 is attached to the outside of the leg plate 18. This internal tooth ratchet plate 30 has internal tooth ratchets coaxial with the circular holes 21 of the leg plates 18, 20.

Further, the internal tooth ratchet plate 30 has a rectangular outer diameter on one side, and has a pair of corner portions 30A, 30.
It has B. These corner portions 30A, 30B are inserted into brackets 32 that are integrally stamped out from the outside of the leg plate 18 and protrude. That is, the bracket 32 is attached to the wall portion 3 that stands perpendicularly to the leg plate 18.
2A and a flat plate portion 32 arranged parallel to the leg plate 18
The corner portions 30A and 30B are accommodated in a substantially triangular recess formed between the leg plate 18 and the leg plate 18. Therefore, while the internal tooth ratchet plate 30 is accommodated in this bracket 32, it is movable in the direction closer to the circular hole 21 than the bracket 32, but cannot be moved in the direction away from the circular hole 21. It is designed to be positioned vertically.

The internal tooth ratchet plate 30 has corner portions 30A,
An extension 30C extends from the opposite side of 30B in the radial direction of the internal tooth ratchet. This extension 30
C is bent at right angles to the center of the internal tooth ratchet plate 30 and inserted into a rectangular groove 33 carved into the leg plates 18, 20. This rectangular groove 3
3 has a lock 33A at its entrance, so that the extension part 30C is fixed to the leg plates 18 and 20 and spanned between the leg plates 18 and 20.
The leg plates 18, 20 are therefore reinforced so that their relative dimensions do not change.

A pair of lock plates 34 and 36 correspond to the internal tooth ratchets of the internal tooth ratchet plate 30 fixed to the leg plates 18 and 20. These lock plates 34, 36 are provided with a recess 40 in the center thereof to receive a rectangular protrusion 38, which is a radial protrusion of the winding shaft 22, so that the overall shape of the lock plates 34, 36 is approximately It is C-shaped.

A lock pawl 44 is formed on a part of the outer periphery of the pair of lock plates 34 and 36 to lock the lock plate 3.
When the lock plates 4 and 36 move in opposite directions, they engage with the internal tooth ratchet of the internal tooth ratchet plate 30 to stop the rotation of the lock plates 34 and 36 about the winding shaft 22. A pair of pins 4 are attached from one side of the lock plates 34 and 36, respectively.
6 protrudes parallel to the winding shaft 22.

A support shaft 48 is disposed coaxially with the rectangular protrusion 38 of the winding shaft 22 so as to rotate integrally with the winding shaft 22. A lock ring 50 is supported on this support shaft 48 so as to be rotatable relative to the support shaft 48, and as shown in FIG. 6, four elongated holes 52 are formed in the lock plate side surface of this lock ring 50. has been done. The pins 46 of the lock plates 34, 36 are accommodated in these elongated holes 52, respectively, so that the pair of lock plates 34, 36 can move in opposite directions by the stroke of the elongated holes 52.

A torsion coil spring 54 is interposed between the lock ring 50 and the support shaft 48, and as shown in FIG. is held on the winding shaft 22. Therefore, the lock ring 50
When the webbing is unwound in the webbing pulling direction of the take-up shaft 22 at a predetermined acceleration or less, it receives a spring biasing force, follows the take-up shaft 22, and rotates integrally with the take-up shaft 22. . However, when the webbing drawing rotation of the take-up shaft 22 exceeds a predetermined value, the torsion coil spring 54 is bent, causing a rotation delay. This rotational delay causes the winding shaft 22 to move the lock plates 34, 36 in opposite directions, as shown in FIG.

A pin 55 projects from the surface of the lock ring 50 facing the lock plates 34, 36 in parallel with the axis of the winding shaft, and forms positioning means together with the rectangular projection 38 of the winding shaft 22. Also lock ring 50
Ratchet teeth 56 are carved on the outer periphery of the leg plate 1.
This corresponds to the pawl 58 which is pivoted to the pole 8. This pawl 58 is pushed up by an inertia ball 62 housed in a case 60 of the leg plate 18 and is brought into engagement with the ratchet teeth 56. This inertia ball 62 separates the pawl 58 from the ratchet teeth 56 when the vehicle is normally running, but when the vehicle acceleration reaches a predetermined value, it moves and engages the pawl 58 with the ratchet teeth 56, thereby pulling out the webbing of the locking wheel 50. The direction rotation is stopped to create a rotation delay between the winding shaft 22 and the winding shaft 22.

Winding device 10 of the present embodiment configured as described above
are the corner portions 30A, 3 of the internal tooth ratchet plate 30.
By inserting 0B into the bracket 32 of the leg plate 18 and fixing the extension portion 30C to the leg plates 18, 20 with the fittings 33A, installation of the internal tooth ratchet plate is completed. In this way, the internal tooth ratchet plate 3
0 has a shape that doubles as a conventional internal tooth ratchet foil and a reinforcing plate, so the number of parts is small and assembly is easy. When getting on the vehicle, the occupant pulls out the webbing 24 from the take-up shaft 22 and attaches it.
Drawer of webbing 24 in normal use condition,
During the winding operation, a large rotational acceleration is not generated on the winding shaft 22, so the locking wheel 50 rotates following the winding shaft 22, and the rotation of the winding shaft 22 to be pulled out is not locked.

If the vehicle is in an emergency situation such as a collision, webbing 2
4 moves violently in the collision direction, the webbing 24 is rapidly pulled out from the winding shaft 22, and a large pulling acceleration is generated at the winding shaft 22.

As a result, the lock wheel 50 lags in rotation with respect to the winding shaft 22, and the rectangular protrusion 38 drives the lock plates 34, 36 in opposite directions through the recess 40, as shown in FIG. It meshes with the internal tooth ratchet foil 30. Therefore, the webbing pull-out rotation of the take-up shaft 22 is stopped instantaneously, and the occupant is securely restrained by the webbing 24, thereby ensuring safety. In this operating state, the internal tooth ratchet plate 30
are securely fixed by the leg plate 18, and the leg plate 18,
Since 20 is reinforced by the extension part 30C,
When the webbing pull-out rotation of the take-up shaft 22 is stopped, the torsional force between the leg plate 18 and the leg plate 20 that acts through the internally toothed ratchet plate 30 is supported by the extension portion 30C, The plates 18 and 20 will not be deformed or damaged.

Further, since the vehicle acceleration that occurs in a vehicle emergency moves the inertia ball 62, the bowl 58 meshes with the ratchet teeth 56 and the rotation of the webbing pull-out of the inertia plate 50 is stopped. Even if a relative rotation occurs between the two and the occupant is not thrown in the direction of the collision, or before the occupant is thrown, the occupant can be restrained by the webbing 24.

When the emergency state of the vehicle ends, the lock plate 34 is removed by slightly winding the webbing 24.
36 is again separated from the internal tooth ratchet to the state shown in FIGS. 1 and 3, and can be used as a normal winding device.

As explained above, the webbing retractor according to the present invention has a structure in which the internal toothed ratchet plate is attached to one leg plate, and the extension part formed integrally with this internal toothed ratchet plate is hung over the other leg plate. Therefore, the number of parts is reduced, ease of assembly is improved, and the structure has excellent effects of improving strength and rigidity.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing the first embodiment of the webbing retractor according to the present invention, Fig. 2 is a left side view of Fig. 1, Fig. 3 is a sectional view taken along the line of Fig. 1, and Fig. 4 is a main view. A partially exploded perspective view, FIG. 5 is an operating diagram showing the locking state of the lock mechanism, and FIG. 6 shows the inertia plate as shown in FIGS.
It is a side view seen in the line direction. 10... Winding device, 12... Frame, 22...
... Winding shaft, 24 ... Webbing, 30 ... Internal tooth ratchet plate, 30A, 30B ... Corner, 3
0C...Extension part, 32...Bracket, 32A...
...Wall part, 32B... Flat plate part, 33... Rectangular groove part,
33A...Me, 34, 36...Lock plate.

Claims (1)

[Claims for Utility Model Registration] (1) A take-up shaft extending from a frame and rotatably supported between a pair of leg plates formed to face each other and winding up occupant restraint webbing; A lock plate that rotates with the shaft and prevents the take-up shaft from rotating in the webbing pulling direction when the rotation is stopped; and an internally toothed ratchet that is attached to one of the pair of leg plates and that engages with the lock plate to stop the rotation. Consisting of a carved main body part, and an extension part integrally extended from the main body part, extended over the other leg plate in a state substantially parallel to the winding shaft, and fixed to the other leg plate, When the rotation of the winding shaft is stopped by the lock plate, the torsional force between the one leg plate and the other leg plate, which acts through the main body part, is supported by the extension part and A webbing take-up device comprising: an internal tooth plate for reinforcing a leg plate; (2) The above-mentioned claim for utility model registration characterized in that the internal tooth plate is attached to the leg plate by being inserted between the leg plate and a bracket whose corner portion integrally projects outward from one of the leg plates. The webbing take-up device according to item 1.